Fat describes cells that are largely made up of saturated fatty compounds - long strings of hydrogen atoms attached to a carbon and oxygen base. Fat has no other purpose in the body other than to store energy - a pound of fat is more than enough energy to provide even an active person with their needs for an entire day. All persons, even the malnourished, have fat cells.
Too much fat causes obesity, which can place strain on the heart as blood vessels must still be in place to provide blood to fat cells.
Certain vitamins, such as Vitamin A and Vitamin D, are fat soluble and are stored in the fat cells of normal people on a healthy diet. However, many toxins are also fat soluble and, ironically, can be released back into the body when the body uses fat.
Fat intake in diet should be restricted, but people of all ages require fat in their diet in order to properly metabolize nutrients.